Required sewage holding-tank capacity for a given POB and passage length per MARPOL Annex IV special-area carriage rules - baseline 70 L/person·day.
Formula
$$ V_{holding} = \text{POB} \cdot d \cdot q_{pc} \cdot (1 + m) $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $POB$ | Persons on board (crew + pax) | pax | muster list |
| $d$ | Retention days required | day | voyage plan |
| $q_{pc}$ | Per-capita generation rate | L/day | MEPC.159(55) guidance |
| $m$ | Safety margin | - | company policy |
Sources
- MARPOL Annex IV.
- MEPC.159(55) STP Guidelines.